Currently, in a known image processing technology, provided that a requirement that image information is correct is met, an encoding-side device compresses an information amount of an image, so that the image adapts to bandwidth and a rate of a channel and is transmitted to a decoding-side device. In analog processing, an image is scanned at a particular rate or a quantity of spatial sampling points is further reduced, a grayscale of a sampling point is reduced (for example, a black and white binary image), and a signal band is compressed by using methods such as compressing bandwidth of a luminance signal and a chrominance signal and frequency interlacing. In digital processing, an image signal on which analog processing is performed is digitized.
As communications technologies are widely applied, users have increasing demands for image-type services, and also have an increasingly high requirement on image quality. Accordingly, processing complexity of the foregoing image processing technology and a requirement on processing performance of the encoding-side device also increase.
It is expected that an image processing technology is provided, to reduce processing complexity of an encoding-side device and reduce a requirement on processing performance of the encoding-side device.